For years we have used Noritz and I still think they're a wonderful product. Problem is, in our area we're having sedimentation issues due to flash heating. We get black grit coming out of the hot side. Noritz tells us that the issue is water quality and that there are only four areas in the country that have this issue. Noritz is the only one in the area that has this problem due to the way that they superheat the water and then mix it back down, apparently no one else does it this way. So, I'm exploring other tankless options. Rinnai has several carriers in the area so I'd like to offer something different as long as its quality. Takagi has given me problems before so I'm not sure about those. I met with a Navien rep (http://www.navienamerica.com/) and I was very impressed with what they could show me. The rep was a former Noritz rep, so he was well aware of our issues and with our needs. My question for you guys is if any of you have put any of these units in? Did you like them? Were they crap? Is there another tankless you would recommend?